CN116137316A

CN116137316A - Electrode assembly, winding method, device, battery cell, battery and electricity utilization device

Info

Publication number: CN116137316A
Application number: CN202111372226.0A
Authority: CN
Inventors: 张小畏; 王治文; 张威; 温裕乾; 唐鸣浩; 张盛武
Original assignee: Contemporary Amperex Technology Co Ltd
Current assignee: Contemporary Amperex Technology Co Ltd
Priority date: 2021-11-18
Filing date: 2021-11-18
Publication date: 2023-05-19
Also published as: WO2023088052A1; EP4354533A1

Abstract

The application relates to the technical field of new energy, in particular to an electrode assembly, a winding method, equipment, a battery monomer, a battery and an electric device, wherein the electrode assembly comprises a first diaphragm, a first pole piece and a second diaphragm which are arranged in a laminated manner; the first pole piece is clamped between the first diaphragm and the second diaphragm, and part edges of two sides of the initial section of the first diaphragm and the second diaphragm are fixedly connected along the width direction of the first pole piece. Through the mode, the problem that initial section alignment is poor when the pole piece is wound in the electrode assembly can be solved.

Description

Electrode assembly, winding method, device, battery cell, battery and electricity utilization device

Technical Field

The application relates to the technical field of new energy, in particular to an electrode assembly, a winding method, equipment, a battery monomer, a battery and an electricity utilization device.

Background

With the rapid development of new energy industry, the production efficiency of the electrode assembly is increasingly required, and the winding mode is widely applied to the production of the electrode assembly due to the characteristics of high efficiency and low cost.

However, when the electrode assembly is wound, the initial section of the pole piece is tension-free, and the situations of feeding deviation of the initial section of the pole piece, poor lamination between the initial section and the diaphragm and the like easily occur, so that the alignment degree of the pole piece is reduced, and the qualification rate of the production of the pole piece is affected.

Disclosure of Invention

In view of the above, the present application provides an electrode assembly, a winding method, a device, a battery cell, a battery and an electric device, so as to solve the problem of poor alignment of an initial section of the electrode assembly when a pole piece is wound.

According to one aspect of the present application, there is provided an electrode assembly including a first separator, a first electrode sheet, and a second separator, which are stacked; the first pole piece is clamped between the first diaphragm and the second diaphragm, and part edges of two sides of the initial section of the first diaphragm and the second diaphragm are fixedly connected along the width direction of the first pole piece.

Through the partial edge fixed connection of the two sides of the first diaphragm and the second diaphragm starting section in the electrode assembly, the first pole piece is clamped between the first diaphragm and the second diaphragm, so that the first diaphragm and the second diaphragm can limit the displacement of the first pole piece along the width direction, but not limit the displacement of the first pole piece along the length direction, thereby not only ensuring the alignment degree of the starting section when the first pole piece is fed, but also ensuring the relative sliding among the first diaphragm, the first pole piece and the second diaphragm during winding, so as to adapt to different winding diameters, ensure the close fitting among the first diaphragm, the first pole piece and the second diaphragm, further ensuring the winding quality of the electrode assembly and improving the winding rate of the electrode assembly.

In an alternative, the first diaphragm is fixedly connected to a portion of the edge on both sides of the ending section of the second diaphragm in the width direction. Through the partial edge fixed connection of the two sides of the tail-closing section of the first diaphragm and the second diaphragm, the alignment of the tail-closing section of the first diaphragm, the first pole piece and the second diaphragm can be effectively ensured, and the winding failure of the electrode assembly caused by the tail-throwing condition is avoided, so that the production rate of the electrode assembly is influenced.

In an alternative, the electrode assembly further comprises a second electrode sheet, the starting section of which is fixedly connected to the second separator. And fixedly connecting the initial section of the second pole piece with the second diaphragm to ensure the alignment degree of the initial section when the second pole piece is fed.

In an alternative mode, the tail-receiving section of the second pole piece is fixedly connected with the second diaphragm. The tail-collecting section of the second pole piece is fixedly connected with the second diaphragm, so that the first diaphragm, the first pole piece, the second diaphragm and the tail-collecting section of the second pole piece can be effectively aligned and tightly attached, and the winding failure of the electrode assembly caused by the tail-throwing condition is avoided, and the production efficiency of the electrode assembly is influenced.

According to another aspect of the present application, there is provided a battery cell including the above-described electrode assembly.

In the battery monomer of this application, through the part edge fixed connection with first diaphragm and the initial section both sides of second diaphragm in the electrode assembly, first pole piece presss from both sides and locates between first diaphragm and the second diaphragm, make first diaphragm and second diaphragm only restrict first pole piece along width direction's displacement, do not restrict first pole piece along length direction's displacement, thereby not only can guarantee the alignment degree of initial section when first pole piece pan feeding, can also take place relative slip between first diaphragm when can guaranteeing to coil, can take place relative slip between first diaphragm and the second diaphragm, with the different winding diameters of adaptation, make closely laminating between first diaphragm, first pole piece and the second diaphragm, thereby guarantee electrode assembly coiling quality, promote electrode assembly's success rate of coiling, and then effectively improve battery monomer's production efficiency.

According to another aspect of the present application, there is provided a battery including the above battery cell.

According to another aspect of the present application, there is provided an electrical device comprising the above battery for providing electrical energy.

According to another aspect of the present application, there is provided an electrode assembly winding method including a first separator, a first electrode sheet, and a second separator, which are stacked, the electrode assembly winding method including: sequentially stacking the first diaphragm, the first pole piece and the initial section of the second diaphragm, and fixedly connecting part edges of two sides of the initial section of the first diaphragm and the edges of two sides of the initial section of the second diaphragm along the width direction of the first pole piece; the first diaphragm, the first pole piece and the second diaphragm are wound.

The electrode assembly comprises a first diaphragm, a second diaphragm, a first pole piece, a second pole piece, a first diaphragm, a second diaphragm, a first electrode assembly, a second electrode assembly, a first electrode assembly and a second electrode assembly.

In an alternative manner, the electrode assembly winding method further includes: and fixedly connecting part edges of two sides of the ending sections of the first diaphragm and the second diaphragm along the width direction. Through the partial edge fixed connection with first diaphragm and second diaphragm end section both sides, can guarantee to press from both sides the first pole piece end section alignment of locating between first diaphragm and the second diaphragm end section and closely laminate with first diaphragm and second diaphragm, avoid the end section of first pole piece to take place to get rid of the condition of tail, cause electrode assembly winding failure.

In an alternative mode, the electrode assembly further comprises a second pole piece, and after the first diaphragm and part of edges on two sides of the initial section of the second diaphragm are fixedly connected, the electrode assembly further comprises: the initial section of the second pole piece is fixedly connected with the second diaphragm. And fixedly connecting the initial section of the second pole piece with the second diaphragm to ensure the alignment degree of the initial section when the second pole piece is fed.

In an alternative manner, the electrode assembly winding method further includes: and fixedly connecting the tail-collecting section of the second pole piece with the second diaphragm. Through with the receipts tail section of second pole piece and second diaphragm fixed connection, guarantee that the receipts tail section of second pole piece aligns and closely laminates with the second diaphragm, avoid the receipts tail section of second pole piece to take place to get rid of the tail and cause electrode assembly winding failure.

According to another aspect of the present application, there is provided an electrode assembly winding apparatus, the electrode assembly including a first separator, a first pole piece, and a second separator, which are sequentially stacked, the electrode assembly winding apparatus including: the first composite mechanism is used for fixedly connecting partial edges of two sides of the first diaphragm and the second diaphragm starting section along the width direction of the first pole piece; and the winding mechanism is arranged at the downstream of the first composite mechanism and is used for winding the first diaphragm, the first pole piece and the second diaphragm to form an electrode assembly.

The first diaphragm and the second diaphragm are fixedly connected with the edges of the two sides of the initial section of the first diaphragm in the electrode assembly through the first compound mechanism, the first pole piece is clamped between the first diaphragm and the second diaphragm, so that the first diaphragm and the second diaphragm only limit the displacement of the first pole piece along the width direction, but not limit the displacement of the first pole piece along the length direction, thereby not only ensuring the alignment degree of the initial section when the first pole piece is fed, but also ensuring the relative sliding among the first diaphragm, the first pole piece and the second diaphragm during winding, so as to adapt to different winding diameters, ensure the close fit among the first diaphragm, the first pole piece and the second diaphragm, further ensure the winding quality of the electrode assembly and improve the winding rate of the electrode assembly.

In an alternative mode, the first composite mechanism comprises a first pressing structure and a second pressing structure which are oppositely arranged, and the first pressing structure is matched with the second pressing structure and is used for fixedly connecting partial edges of two sides of the initial section of the first diaphragm and the second diaphragm along the width direction. Through the cooperation of first pressfitting structure and second pressfitting structure, realize the quick connect fixed to the partial edge of first diaphragm and second diaphragm initial segment both sides, and stable in structure is reliable after fixed connection.

In an alternative manner, the first pressing structure includes a pressing portion and a thermocompression bonding portion, the thermocompression bonding portion is disposed at two ends of the pressing portion in the width direction, and the thermocompression bonding portion is configured to protrude from the pressing portion, and the thermocompression bonding portion is configured to thermocompression bond partial edges of both sides of the initial section of the first diaphragm and the second diaphragm. The hot pressing composite part protrudes out of the pressing part, so that the full hot pressing composite can be carried out on part of edges of two sides of the initial section of the first diaphragm and the second diaphragm, and the connection stability of the first diaphragm and the second diaphragm is further ensured.

In an alternative manner, the heat and pressure composite part protrudes from the pressing part in a ring shape. Through being annular protrusion with hot pressing compound portion and setting up in pressing part, guarantee that hot pressing compound portion is pressing first diaphragm and second diaphragm in, can also take place to rotate, realize driving the function of electrode assembly pan feeding.

In an alternative mode, the electrode assembly further comprises a second pole piece, the electrode assembly winding device further comprises a second compounding mechanism, and the second compounding mechanism is arranged between the first compounding mechanism and the winding mechanism and is used for fixedly connecting the initial section of the second pole piece with the second diaphragm. Through setting up second compound mechanism, realize the fixed connection between second pole piece initial segment and the second diaphragm, guarantee the alignment degree of second pole piece.

The foregoing description is only an overview of the technical solutions of the present application, and may be implemented according to the content of the specification in order to make the technical means of the present application more clearly understood, and in order to make the above-mentioned and other objects, features and advantages of the present application more clearly understood, the following detailed description of the present application will be given.

Drawings

Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are only for purposes of illustrating the preferred embodiments and are not to be construed as limiting the application. Also, like reference numerals are used to designate like parts throughout the figures. In the drawings:

fig. 1 is a schematic structural diagram of a vehicle according to an embodiment of the present application;

fig. 2 is a schematic diagram of an explosion structure of a battery according to an embodiment of the present application;

fig. 3 is an exploded view of a battery cell according to an embodiment of the present disclosure;

fig. 4 is a schematic exploded view of an electrode assembly tail-receiving section according to an embodiment of the present disclosure;

FIG. 5 is a schematic view of the structure of an initial section of an electrode assembly according to an embodiment of the present disclosure;

fig. 6 is a schematic structural view of an electrode assembly according to an embodiment of the present application;

Fig. 7 is a schematic flow chart of an electrode assembly winding method according to an embodiment of the present disclosure;

fig. 8 is a flowchart of an electrode assembly winding method according to another embodiment of the present application;

fig. 9 is a schematic structural view of an electrode assembly winding apparatus provided in an embodiment of the present application;

fig. 10 is a schematic structural view of an electrode assembly winding apparatus according to another embodiment of the present application;

fig. 11 is a schematic structural view of a first composite mechanism in an electrode assembly winding apparatus according to an embodiment of the present application;

fig. 12 is a schematic structural view of a second composite mechanism in the electrode assembly winding apparatus according to the embodiment of the present application.

Reference numerals in the specific embodiments are as follows:

a vehicle 1000;

battery 100, controller 200, motor 300;

a case 10, a first portion 11, a second portion 12;

a battery cell 20, an end cap 21, an electrode terminal 21a, and a case 22;

electrode assembly 23, tab 23a, first separator 231, first pole piece 232, second separator 233, second pole piece 234, first region 235, second region 236;

the electrode assembly winding apparatus 500, the first lamination mechanism 510, the first lamination structure 511, the pressing portion 5111, the hot press lamination portion 5112, the second lamination structure 512, the winding mechanism 520, the second lamination mechanism 530, the third lamination structure 531, the fourth lamination structure 532, the feeding mechanism 540, and the deviation rectifying mechanism 550.

Detailed Description

Embodiments of the technical solutions of the present application will be described in detail below with reference to the accompanying drawings. The following examples are only for more clearly illustrating the technical solutions of the present application, and thus are only examples, and are not intended to limit the scope of protection of the present application.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application; the terms "comprising" and "having" and any variations thereof in the description and claims of the present application and in the description of the figures above are intended to cover non-exclusive inclusions.

In the description of the embodiments of the present application, the technical terms "first," "second," etc. are used merely to distinguish between different objects and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated, a particular order or a primary or secondary relationship. In the description of the embodiments of the present application, the meaning of "plurality" is two or more unless explicitly defined otherwise.

Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the present application. The appearances of such phrases in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. Those of skill in the art will explicitly and implicitly appreciate that the embodiments described herein may be combined with other embodiments.

In the description of the embodiments of the present application, the term "and/or" is merely an association relationship describing an association object, which means that three relationships may exist, for example, a and/or B may mean: there are three cases, a, B, a and B simultaneously. In addition, the character "/" herein generally indicates that the front and rear associated objects are an "or" relationship.

In the description of the embodiments of the present application, the term "plurality" refers to two or more (including two), and similarly, "plural sets" refers to two or more (including two), and "plural sheets" refers to two or more (including two).

In the description of the embodiments of the present application, the orientation or positional relationship indicated by the technical terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. are based on the orientation or positional relationship shown in the drawings, and are merely for convenience of describing the embodiments of the present application and for simplifying the description, rather than indicating or implying that the apparatus or element referred to must have a specific orientation, be configured and operated in a specific orientation, and therefore should not be construed as limiting the embodiments of the present application.

In the description of the embodiments of the present application, unless explicitly specified and limited otherwise, the terms "mounted," "connected," "secured" and the like are to be construed broadly and may be, for example, fixedly connected, detachably connected, or integrally formed; or may be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communicated with the inside of two elements or the interaction relationship of the two elements. The specific meaning of the above terms in the embodiments of the present application will be understood by those of ordinary skill in the art according to the specific circumstances.

Currently, the more widely the battery is used in view of the development of market situation. The battery is not only applied to energy storage power supply systems such as hydraulic power, firepower, wind power and solar power stations, but also widely applied to electric vehicles such as electric bicycles, electric motorcycles, electric automobiles, and the like, as well as a plurality of fields such as military equipment, aerospace, and the like. With the continuous expansion of the battery application field, the market demand thereof is also continuously expanding.

The electrode assembly is an important component in the battery, and has higher requirements on production efficiency, and the winding mode has the advantages of high efficiency and low cost, so that the electrode assembly is widely applied to the production of the electrode assembly.

When the electrode assembly is wound, the starting section and the tail collecting section of the pole piece are free of tension, so that when the starting section of the pole piece is fed, the offset condition is easy to occur, the tail collecting section is easy to occur, and poor alignment of the pole piece is caused. Meanwhile, the starting section and the tail-collecting section of the pole piece are in an uncontrolled state in the winding process, so that the problem of poor lamination of the pole piece and the diaphragm is easy to occur.

In order to avoid the problems, the existing electrode assembly generally performs complete hot-pressing compounding between the pole piece and the diaphragm before winding, so that the pole piece and the diaphragm are tightly attached and connected, and the alignment degree of the beginning section and the tail section of the pole piece is ensured.

However, the invention of the application notes that when the winding is performed, due to the different winding diameters of the pole pieces and the diaphragms of different layers, after the pole pieces and the diaphragms are completely compounded by hot pressing before the winding, the interaction force between the pole pieces and the diaphragms of different layers is gradually increased along with the increase of the winding layer number in the winding process, so that the pole pieces and the diaphragms are wrinkled, even the diaphragms are broken, and the winding is failed.

Based on this, this application provides an electrode assembly, coiling method, equipment, battery monomer, battery and power consumption device, through the part edge fixed connection with the first diaphragm in the electrode assembly and second diaphragm starter both sides, first pole piece presss from both sides and locates between first diaphragm and the second diaphragm, make first diaphragm and second diaphragm only restrict the displacement of first pole piece along width direction, the displacement of first pole piece along length direction is not restricted, thereby not only can guarantee the alignment degree of starter when first pole piece pan feeding, can also guarantee to take place relative slip between first diaphragm during the coiling, first pole piece and the second diaphragm, with the different coiling diameters of adaptation, closely laminate between messenger's first diaphragm, first pole piece and the second diaphragm, thereby guarantee electrode assembly coiling quality, promote electrode assembly coiling's success rate, and then effectively improve electrode assembly's production efficiency.

The battery disclosed by the embodiment of the application can be used in electric devices such as vehicles, ships or aircrafts, but is not limited to the batteries.

The embodiment of the application provides an electricity utilization device using a battery as a power supply, wherein the electricity utilization device can be, but is not limited to, a mobile phone, a tablet, a notebook computer, an electric toy, an electric tool, a battery car, an electric car, a ship, a spacecraft and the like. Among them, the electric toy may include fixed or mobile electric toys, such as game machines, electric car toys, electric ship toys, electric plane toys, and the like, and the spacecraft may include planes, rockets, space planes, and spacecraft, and the like.

For convenience of description, the following embodiment will take an electric device according to an embodiment of the present application as an example of the vehicle 1000.

Referring to fig. 1, fig. 1 is a schematic structural diagram of a vehicle 1000 according to some embodiments of the present application. The vehicle 1000 may be a fuel oil vehicle, a gas vehicle or a new energy vehicle, and the new energy vehicle may be a pure electric vehicle, a hybrid vehicle or a range-extended vehicle. The battery 100 is provided in the interior of the vehicle 1000, and the battery 100 may be provided at the bottom or the head or the tail of the vehicle 1000. The battery 100 may be used for power supply of the vehicle 1000, for example, the battery 100 may be used as an operating power source of the vehicle 1000. The vehicle 1000 may also include a controller 200 and a motor 300, the controller 200 being configured to control the battery 100 to power the motor 300, for example, for operating power requirements during start-up, navigation, and travel of the vehicle 1000.

In some embodiments of the present application, battery 100 may not only serve as an operating power source for vehicle 1000, but may also serve as a driving power source for vehicle 1000, instead of or in part instead of fuel oil or natural gas, to provide driving power for vehicle 1000.

Referring to fig. 2, fig. 2 is a schematic diagram illustrating an exploded structure of a battery 100 according to some embodiments of the present application. The battery 100 includes a case 10 and a battery cell 20, and the battery cell 20 is accommodated in the case 10. The case 10 is used to provide an accommodating space for the battery cell 20, and the case 10 may have various structures. In some embodiments, the case 10 may include a first portion 11 and a second portion 12, the first portion 11 and the second portion 12 being overlapped with each other, the first portion 11 and the second portion 12 together defining an accommodating space for accommodating the battery cell 20. The second portion 12 may be a hollow structure with one end opened, the first portion 11 may be a plate-shaped structure, and the first portion 11 covers the opening side of the second portion 12, so that the first portion 11 and the second portion 12 together define a containing space; the first portion 11 and the second portion 12 may be hollow structures each having an opening at one side, and the opening side of the first portion 11 is engaged with the opening side of the second portion 12. Of course, the case 10 formed by the first portion 11 and the second portion 12 may be of various shapes, such as a cylinder, a rectangular parallelepiped, or the like.

In the battery 100, the plurality of battery cells 20 may be connected in series, parallel or a series-parallel connection, wherein the series-parallel connection refers to that the plurality of battery cells 20 are connected in series or parallel. The plurality of battery cells 20 can be directly connected in series or in parallel or in series-parallel, and then the whole formed by the plurality of battery cells 20 is accommodated in the box 10; of course, the battery 100 may also be a battery module formed by connecting a plurality of battery cells 20 in series or parallel or series-parallel connection, and a plurality of battery modules are then connected in series or parallel or series-parallel connection to form a whole and are accommodated in the case 10. The battery 100 may further include other structures, for example, the battery 100 may further include a bus member for making electrical connection between the plurality of battery cells 20.

Wherein each battery cell 20 may be a secondary battery or a primary battery; but not limited to, lithium sulfur batteries, sodium ion batteries, or magnesium ion batteries. The battery cell 20 may be in the shape of a cylinder, a flat body, a rectangular parallelepiped, or other shapes, etc.

Referring to fig. 3, fig. 3 is a schematic exploded view of a battery cell 20 in the battery 100 according to some embodiments of the present application. The battery cell 20 refers to the smallest unit constituting the battery. As shown in fig. 3, the battery cell 20 includes an end cap 21, a case 22, an electrode assembly 23, and other functional components.

The end cap 21 refers to a member that is covered at the opening of the case 22 to isolate the internal environment of the battery cell 20 from the external environment. Without limitation, the shape of the end cap 21 may be adapted to the shape of the housing 22 to fit the housing 22. Optionally, the end cover 21 may be made of a material (such as an aluminum alloy) with a certain hardness and strength, so that the end cover 21 is not easy to deform when being extruded and collided, so that the battery cell 20 can have higher structural strength, and the safety performance can be improved. The end cap 21 may be provided with a functional member such as an electrode terminal 21 a. The electrode terminal 21a may be used to be electrically connected with the electrode assembly 23 for outputting or inputting electric power of the battery cell 20. In some embodiments, the end cap 21 may also be provided with a pressure relief mechanism for relieving the internal pressure when the internal pressure or temperature of the battery cell 20 reaches a threshold. The material of the end cap 21 may be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., which is not particularly limited in the embodiment of the present application. In some embodiments, insulation may also be provided on the inside of the end cap 21, which may be used to isolate electrical connection components within the housing 22 from the end cap 21 to reduce the risk of short circuits. By way of example, the insulation may be plastic, rubber, or the like.

The case 22 is an assembly for cooperating with the end cap 21 to form an internal environment of the battery cell 20, wherein the formed internal environment may be used to accommodate the electrode assembly 23, the electrolyte, and other components. The case 22 and the end cap 21 may be separate members, and an opening may be provided in the case 22, and the interior of the battery cell 20 may be formed by covering the opening with the end cap 21 at the opening. The case 22 may be formed by integrating the end cap 21 and the case 22 into one body, but not limited thereto, and may be formed in various shapes and various sizes, such as rectangular parallelepiped, cylindrical, hexagonal prism, etc. Specifically, the shape of the case 22 may be determined according to the specific shape and size of the electrode assembly 23. The material of the housing 22 may be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., which is not particularly limited in the embodiments of the present application.

The electrode assembly 23 is a component in which electrochemical reactions occur in the battery cell 20. One or more electrode assemblies 23 may be contained within the housing 22. The electrode assembly 23 is mainly formed by winding or stacking a positive electrode sheet and a negative electrode sheet, and a separator is generally provided between the positive electrode sheet and the negative electrode sheet. The portions of the positive electrode sheet and the negative electrode sheet having the active material constitute the main body portion of the electrode assembly, and the portions of the positive electrode sheet and the negative electrode sheet having no active material constitute the tab 23a, respectively. The positive electrode tab and the negative electrode tab may be located at one end of the main body portion together or located at two ends of the main body portion respectively. During charge and discharge of the battery, the positive electrode active material and the negative electrode active material react with the electrolyte, and the tab 23a is connected to the electrode terminal to form a current loop.

According to one aspect of the present application, an electrode assembly is provided. Referring specifically to fig. 4 and 5, an exploded end section of an electrode assembly 23 according to an embodiment of the present application is shown in fig. 4, and a beginning section of the electrode assembly 23 is shown in fig. 5. The electrode assembly 23 includes a first separator 231, a first electrode sheet 232, and a second separator 233, which are stacked. The first pole piece 232 is sandwiched between the first diaphragm 231 and the second diaphragm 233, and along the width direction of the first pole piece 232, the first diaphragm 231 is fixedly connected with part of the edges of the two sides of the initial section of the second diaphragm 233.

The width direction of the first pole piece 232 is the x-axis direction shown in the figure.

It should be noted that, because the head of the first pole piece 232 may be located at the middle sections of the first membrane 231 and the second membrane 233 during winding, the initial section in the present application refers to a section where the head of the first pole piece 232 is attached to the first membrane 231 and the second membrane 233 after feeding, and the tail end section refers to a section where the tail of the first pole piece 232 is attached to the first membrane 231 and the second membrane 233.

As shown in fig. 5, the area of the fixed connection of the first membrane 231 and the second membrane 233 is the first area 235 in the drawing. The first region 235 is the portion of the first diaphragm 231 and the second diaphragm 233 that exceeds the first pole piece 232. Specifically, the first diaphragm 231 and the second diaphragm 233 may be fixed by a thermocompression bonding mechanism after thermocompression bonding on both sides, or may be fixed by an adhesive mechanism after bonding. Of course, other fixing connection methods may be used, which is not limited in the present application.

Through the fixed connection of the partial edges of the two sides of the initial section of the first diaphragm 231 and the second diaphragm 233 in the electrode assembly 23, the first pole piece 232 is clamped between the first diaphragm 231 and the second diaphragm 233, so that the first diaphragm 231 and the second diaphragm 233 only limit the displacement of the first pole piece 232 along the width direction, but not limit the displacement of the first pole piece 232 along the length direction, thereby not only ensuring the alignment degree of the initial section when the first pole piece 232 is fed, but also ensuring the relative sliding among the first diaphragm 231, the first pole piece 232 and the second diaphragm 233 during winding so as to adapt to different winding diameters, so that the first diaphragm 231, the first pole piece 232 and the second diaphragm 233 are tightly attached, the winding quality of the electrode assembly 23 is ensured, and the winding rate of the electrode assembly 23 is improved.

Referring to fig. 6, a structure of an electrode assembly 23 according to an embodiment of the present application is shown. According to some embodiments of the present application, the first diaphragm 231 is fixedly connected to a part of the edge of the two sides of the ending section of the second diaphragm 233 in the width direction.

Likewise, through the fixed connection of the edges of the two sides of the ending section of the first diaphragm 231 and the second diaphragm 233, the alignment and the close attachment of the ending sections of the first diaphragm 231, the first pole piece 232 and the second diaphragm 233 can be effectively ensured, and the winding failure of the electrode assembly caused by the tail flicking condition is avoided, so that the production efficiency of the electrode assembly 23 is influenced.

Referring again to fig. 4 and 5, in accordance with some embodiments of the present application, the electrode assembly 23 further includes a second electrode piece 234, and a starting section of the second electrode piece 234 is fixedly connected to the second separator 233.

As shown in fig. 5, the area where the second pole piece 234 is fixedly connected to the second diaphragm 233 is a second area 236 in the drawing.

The initial section of the second pole piece 234 is fixedly connected with the second diaphragm 233, so that the alignment degree of the initial section is ensured when the second pole piece 234 is fed, only the initial section of the second pole piece 234 is fixed during winding, and the rest part can slide along with the winding relative to the second diaphragm 233 to the ending section so as to adapt to the corresponding winding diameter, so that the second pole piece 234 and the second diaphragm 233 are tightly attached.

Referring again to fig. 6, according to some embodiments of the present application, the tail-receiving section of the second pole piece 234 is fixedly connected to the second diaphragm 233.

The tail-collecting section of the second pole piece 234 is fixedly connected with the second diaphragm 233, so that the alignment and close attachment of the tail-collecting sections of the first diaphragm 231, the first pole piece 232, the second diaphragm 233 and the second pole piece 234 can be effectively ensured, and the winding failure of the electrode assembly caused by the tail-throwing condition is avoided.

According to another aspect of the embodiments of the present application, there is also provided a battery cell including the above-described electrode assembly 23.

In the battery monomer of this application, through the partial edge fixed connection with the first diaphragm 231 in the electrode assembly 23 and the initial section both sides of second diaphragm 233, first pole piece 232 presss from both sides between locating first diaphragm 231 and second diaphragm 233, make first diaphragm 231 and second diaphragm 233 only restrict the displacement of first pole piece 232 along width direction, do not restrict the displacement of first pole piece 232 along length direction, thereby not only can guarantee the alignment degree of initial section when first pole piece 232 pan feeding, can also take place the relative slip between first diaphragm 231 when can guaranteeing to coil, first pole piece 232 and the second diaphragm 233, with the different coiling diameters of adaptation, closely laminate between messenger's first diaphragm 231, first pole piece 232 and the second diaphragm 233, thereby guarantee electrode assembly 23 coiling quality, promote electrode assembly 23 coiling's success rate, and then effectively improve battery monomer's production efficiency.

According to another aspect of the present application, there is also provided a battery including the above battery cell.

In the battery, a plurality of battery monomers can be connected in series or in parallel or in series-parallel connection, and the series-parallel connection means that the plurality of battery monomers are connected in series or in parallel. The plurality of battery monomers can be directly connected in series or in parallel or in series-parallel, and then the whole formed by the plurality of battery monomers is accommodated in the box body; of course, the battery can also be in a form of a battery module formed by connecting a plurality of battery monomers in series or parallel or series-parallel connection, and then connecting a plurality of battery modules in series or parallel or series-parallel connection to form a whole body and accommodating the whole body in the box body. The battery may further include other structures, for example, a bus member for making electrical connection between the plurality of battery cells.

According to another aspect of the present application, there is also provided an electric device including the above battery for providing electric energy.

The power device may be, but is not limited to, a cell phone, tablet, notebook computer, electric toy, electric tool, battery car, electric car, ship, spacecraft, etc. Among them, the electric toy may include fixed or mobile electric toys, such as game machines, electric car toys, electric ship toys, electric plane toys, and the like, and the spacecraft may include planes, rockets, space planes, and spacecraft, and the like.

In accordance with another aspect of the present application, an electrode assembly winding method is provided, and referring specifically to fig. 7, a flow of an electrode assembly winding method according to an embodiment of the present application is shown. Wherein the electrode assembly includes a first separator, a first pole piece, and a second separator, the electrode assembly winding method includes:

s10: sequentially stacking the first diaphragm, the first pole piece and the initial section of the second diaphragm, and fixedly connecting part edges of two sides of the initial section of the first diaphragm and the edges of two sides of the initial section of the second diaphragm along the width direction of the first pole piece;

s20: the first diaphragm, the first pole piece and the second diaphragm are wound.

The first diaphragm and the second diaphragm are fixedly connected with part of edges on two sides of the initial section of the first diaphragm and the second diaphragm in the electrode assembly, the first pole piece is clamped between the first diaphragm and the second diaphragm, so that the first diaphragm and the second diaphragm only limit the displacement of the first pole piece along the width direction, but not limit the displacement of the first pole piece along the length direction, thereby ensuring the alignment degree of the initial section when the first pole piece is fed, ensuring the relative sliding among the first diaphragm, the first pole piece and the second diaphragm during winding, adapting different winding diameters, tightly attaching the first diaphragm, the first pole piece and the second diaphragm, ensuring the winding quality of the electrode assembly and improving the winding rate of the electrode assembly.

Referring to fig. 8, a flow chart of an electrode assembly winding method according to another embodiment of the present application is shown. According to some embodiments of the present application, the electrode assembly winding method further includes:

s30: and fixedly connecting part edges of two sides of the ending sections of the first diaphragm and the second diaphragm along the width direction.

Through the partial edge fixed connection with first diaphragm and second diaphragm end section both sides, can guarantee to press from both sides the first pole piece end section alignment of locating between first diaphragm and the second diaphragm end section and closely laminate with first diaphragm and second diaphragm, avoid the end section of first pole piece to take place to get rid of the condition of tail, cause electrode assembly winding failure.

Referring again to fig. 8, in accordance with some embodiments of the present application, the electrode assembly further includes a second electrode sheet, and after step S10, further includes:

step S11: the initial section of the second pole piece is fixedly connected with the second diaphragm.

The initial section of the second pole piece is fixedly connected with the second diaphragm, so that the alignment degree of the initial section during feeding of the second pole piece is ensured, and meanwhile, the second pole piece can slide relative to the second diaphragm during winding so as to adapt to the corresponding winding diameter.

It will be appreciated that the order of steps S11 and S10 may be reversed. Other steps can be exchanged without affecting the effect.

Referring again to fig. 8, according to some embodiments of the present application, the electrode assembly winding method further includes:

s40: and fixedly connecting the tail-collecting section of the second pole piece with the second diaphragm.

Through with the receipts tail section of second pole piece and second diaphragm fixed connection, guarantee that the receipts tail section of second pole piece aligns and closely laminates with the second diaphragm, avoid the receipts tail section of second pole piece to take place to get rid of the tail, cause electrode assembly's rejection.

In accordance with another aspect of an embodiment of the present application, there is also provided an electrode assembly winding apparatus, and more particularly, to fig. 9, which illustrates a structure of an electrode assembly winding apparatus 500 according to an embodiment of the present application. The electrode assembly 23 includes a first separator 231, a first electrode sheet 232, and a second separator 233, which are sequentially stacked, and the electrode assembly winding apparatus 500 includes: a first compounding mechanism 510 and a winding mechanism 520. The first compound mechanism 510 is configured to fixedly connect partial edges of two sides of the initial sections of the first diaphragm 231 and the second diaphragm 233 along the width direction of the first pole piece 232. A winding mechanism 520 is disposed downstream of the first composite mechanism 510 for winding the first separator 231, the first pole piece 232, and the second separator 233 to form the electrode assembly 23.

The first diaphragm 231 and the second diaphragm 233 in the electrode assembly 23 are fixedly connected with the partial edges of the two sides of the initial section of the first diaphragm 231 and the second diaphragm 233 through the first compound mechanism 510, and the first pole piece 232 is clamped between the first diaphragm 231 and the second diaphragm 233, so that the displacement of the first pole piece 232 along the width direction is only limited, the displacement of the first pole piece 232 along the length direction is not limited, the alignment degree of the initial section of the first pole piece 232 during feeding can be ensured, the relative sliding among the first diaphragm 231, the first pole piece 232 and the second diaphragm 233 during winding can be ensured, different winding diameters can be adapted, the first diaphragm 231, the first pole piece 232 and the second diaphragm 233 are tightly attached, the winding quality of the electrode assembly 23 is ensured, the winding success rate of the electrode assembly 23 is improved, and the production efficiency of the electrode assembly 23 is further effectively improved.

Referring to fig. 10, there is shown a structure of an electrode assembly winding apparatus 500 according to another embodiment of the present application. In other embodiments of the present application, when the initial section of the second pole piece 234 and the second diaphragm 233 pass through the second compounding mechanism 530, the initial section of the second pole piece 234 may be fixedly connected with the second diaphragm 233 through the second compounding mechanism 530, and when the initial section of the second diaphragm 233 fixed with the second pole piece 234, the first pole piece 232 and the initial section of the first diaphragm 231 pass through the first compounding mechanism 510, part of edges on both sides of the initial sections of the first diaphragm 231 and the second diaphragm 233 may be fixedly connected through the first compounding mechanism 510, and then wound by the winding mechanism 520.

Referring to fig. 11, a structure of a first composite mechanism 510 in an electrode assembly winding apparatus 500 according to an embodiment of the present application is shown. According to some embodiments of the present application, the first compounding mechanism 510 includes a first press-fit structure 511 and a second press-fit structure 512 that are disposed opposite to each other. The first pressing structure 511 and the second pressing structure 512 are matched, and are used for fixedly connecting part of edges of two sides of the initial section of the first diaphragm 231 and the second diaphragm 233 along the width direction of the first pole piece 232.

When the first pressing structure 511 and the second pressing structure 512 move in opposite directions, the first diaphragm 231, the first pole piece 232 and the second diaphragm 233 are clamped between the first pressing structure 511 and the second pressing structure 512, so that part of edges on two sides of the initial section of the first diaphragm 231 and the second diaphragm 233 are fixedly connected.

As shown in fig. 11, the first pressing structure 511 and the second pressing structure 512 may each be cylindrical, the first diaphragm 231, the first pole piece 232 and the second diaphragm 233 are clamped by the annular side surface of the first pressing structure 511 and the annular side surface of the second pressing structure 512, and the first diaphragm 231, the first pole piece 232 and the second diaphragm 233 may be moved by setting the two sides of the first pressing structure 511 as hot pressing portions to perform hot pressing composite fixing on part of the edges of the two sides of the initial section of the first diaphragm 231 and the second diaphragm 233, and simultaneously the first pressing structure 511 and the second pressing structure 512 may also rotate.

It will be appreciated that the first pressing structure 511 and the second pressing structure 512 may be square or other shapes, and after the partial edges of the two sides of the initial sections of the first diaphragm 231 and the second diaphragm 233 move between the first pressing structure 511 and the second pressing structure 512, the first pressing structure 511 and the second pressing structure 512 move towards each other to press and fix the partial edges of the two sides of the initial sections of the first diaphragm 231 and the second diaphragm 233, and then the first diaphragm 231 and the second diaphragm 233, which are clamped with the first pole piece 232 and fixed by pressing, move away from each other to reset, and then move again to feed.

Specifically, the first pressing structure 511 and the second pressing structure 512 move towards each other, which may be that the first pressing structure 511 moves towards the second pressing structure 512, the second pressing structure 512 moves towards the first pressing structure 511, or both the first pressing structure 511 moves towards the second pressing structure 512 and the second pressing structure 512 moves towards the first pressing structure 511, and the specific moving manner may be that the first pressing structure and the second pressing structure 512 are driven by an air cylinder, an electric cylinder or a screw rod, or may be manual operation. When the initial sections of the first diaphragm 231 and the second diaphragm 233 pass through the first composite mechanism 510, the first pressing structure 511 and the second pressing structure 512 are driven to move in opposite directions to press and connect part of edges of two sides of the initial sections of the first diaphragm 231 and the second diaphragm 233, and after the pressing is completed, the first pressing structure 511 and the second pressing structure 512 move in opposite directions to ensure that the first diaphragm 231 and the second diaphragm 233 are normally fed. If the edges of the two sides of the ending sections of the first diaphragm 231 and the second diaphragm 233 need to be fixedly connected, the above steps may be repeated again when the ending sections of the first diaphragm 231 and the second diaphragm 233 pass through the first composite mechanism 510.

Through the cooperation of the first pressing structure 511 and the second pressing structure 512, the quick connection and fixation of the edges of the two sides of the initial section of the first diaphragm 231 and the second diaphragm 233 are realized, and the structure after the fixed connection is stable and reliable.

With continued reference to fig. 11, according to some embodiments of the present application, the first pressing structure 511 includes a pressing portion 5111 and a thermal lamination portion 5112, the thermal lamination portion 5112 is disposed at two ends of the pressing portion 5111 along the width direction, and the thermal lamination portion 5112 is configured to protrude from the pressing portion 5111, and the thermal lamination portion 5112 is used for thermal lamination of edges at two sides of the initial sections of the first membrane 231 and the second membrane 233.

Specifically, the heat and pressure composite portion 5112 is configured to protrude from the pressing portion 5111, that is, there is a height difference h as shown in fig. 11 between the heat and pressure composite portion 5112 and the pressing portion 5111. The hot-press compounding manner can quickly fix the partial edges of the two sides of the initial sections of the first diaphragm 231 and the second diaphragm 233 to each other, improve winding efficiency, and ensure structural integrity of the first diaphragm 231, the first pole piece 232 and the second diaphragm 233.

The thermo-compression composite portion 5112 has a high temperature surface, and heat is transferred to the first diaphragm 231 or the second diaphragm 233 by pressing the surface of the edge of the first diaphragm 231 or the second diaphragm 233 by the abutment of the high temperature surface, so that the first diaphragm 231 and the second diaphragm 233 are fixed by thermo-compression composite between the partial edges of both sides of the initial section.

The middle pressing portion 5111 can be used for flattening the middle portion of the first diaphragm 231, the first pole piece 232 and the second diaphragm 233, the hot pressing composite portions 5112 at two ends are used for carrying out hot pressing composite on part edges at two sides of the initial section of the first diaphragm 231 and the second diaphragm 233, after the hot pressing composite is carried out on part edges at two sides of the initial section of the first diaphragm 231 and the second diaphragm 233, the middle portion of the first diaphragm 231, the middle portion of the second diaphragm 233 and the middle portion of the first pole piece 232 are smooth and tightly attached, the hot pressing composite portions 5112 are arranged in the pressing portion 5111 in a protruding mode, the full hot pressing composite can be carried out on part edges at two sides of the initial section of the first diaphragm 231 and the second diaphragm 233, and stability of connection of the first diaphragm 231 and the second diaphragm 233 is further guaranteed. It is understood that in some embodiments, the pressing portion 5111 may not contact the middle portions of the first diaphragm 231, the first pole piece 232, and the second diaphragm 233, and only serve to connect the two thermocompression bonding portions 5112.

As shown in fig. 11, in some embodiments, the pressing portion 5111 and the thermo-compression compound portion 5112 may be disposed apart to avoid thermo-compression of the edges of the first and

second diaphragms

231 and 233, and also the edges of the intermediate first pole piece 232.

With continued reference to fig. 11, according to some embodiments of the present application, the thermo-compression compound portion 5112 protrudes annularly from the pressing portion 5111.

Through being annular protrusion with hot pressing composite portion 5112 and setting up in pressing portion 5111, guarantee that hot pressing composite portion 5112 can also take place to rotate when pressing first diaphragm 231 and second diaphragm 233, improve machining efficiency, can realize driving electrode assembly 23 pan feeding's function simultaneously.

Referring to fig. 12, a structure of a second composite mechanism 530 in an electrode assembly winding apparatus 500 according to an embodiment of the present application is shown. According to some embodiments of the present application, the electrode assembly 23 further comprises a second pole piece 234, and the electrode assembly winding apparatus 500 further comprises a second compounding mechanism 530, the second compounding mechanism 530 being disposed between the first compounding mechanism 510 and the winding mechanism 520 for fixedly connecting the beginning section of the second pole piece 234 with the second separator 233.

As shown in fig. 12, the second compounding mechanism 530 may include a third press structure 531 and a fourth press structure 532, and the third press structure 531 and the fourth press structure 532 thermally press-compound the initial section of the second pole piece 234 with the second diaphragm 233 when moving toward each other.

The third pressing structure 531 and the fourth pressing structure 532 may be cylindrical, and the annular side surface of the third pressing structure 531 and the annular side surface of the fourth pressing structure 532 clamp and thermally press the initial section of the second pole piece 234 and the second diaphragm 233 to be compounded, so that the initial section of the second pole piece 234 and the second diaphragm 233 are fixedly connected, and meanwhile, the third pressing structure 531 and the fourth pressing structure 532 rotate, so that the second pole piece 234 and the second diaphragm 233 are moved to be fed.

Specifically, the movement of the third pressing structure 531 and the fourth pressing structure 532 in opposite directions may be that the third pressing structure 531 moves towards the fourth pressing structure 532, the fourth pressing structure 532 moves towards the third pressing structure 531, or both the movement of the third pressing structure 531 towards the fourth pressing structure 532 and the movement of the fourth pressing structure 532 towards the third pressing structure 531 are performed, and the specific movement may be driven by an air cylinder, an electric cylinder or a screw rod, or may be manual operation. When the initial section of the second diaphragm 233 and the second pole piece 234 pass through the second composite mechanism 530, the third pressing structure 531 and the fourth pressing structure 532 are driven to move in opposite directions to press the initial section of the second pole piece 234 and the second diaphragm 233, and after the pressing is completed, the third pressing structure 531 and the fourth pressing structure 532 are moved away from each other to ensure that the second diaphragm 233 and the second pole piece 234 are normally fed. If the tail-collecting section of the second pole piece 234 is fixedly connected with the second diaphragm 233, the above steps are repeated when the tail-collecting section of the second diaphragm 233 and the second pole piece 234 pass through the second composite mechanism 530.

By arranging the second compound mechanism 530, the fixed connection between the initial section of the second pole piece 234 and the second diaphragm 233 is realized, and the alignment degree of the second pole piece 234 is ensured.

Referring again to fig. 9, according to some embodiments of the present application, the electrode assembly winding apparatus 500 further includes a plurality of feeding mechanisms 540 for respectively feeding the first separator 231, the first pole piece 232, the second separator 233, and the second pole piece 234.

Specifically, the feeding mechanism 540 may be a roller, where the first diaphragm 231, the first pole piece 232, the second diaphragm 233, and the second pole piece 234 are disposed on the roller, and the first diaphragm 231, the first pole piece 232, the second diaphragm 233, and the second pole piece 234 are driven to move for feeding by the rotation of the roller.

Through setting up pan feeding mechanism 540, realize that first diaphragm 231, first pole piece 232, second diaphragm 233 and second pole piece 234 remove the pan feeding, the automation of being convenient for electrode assembly 23 is convoluteed, helps improving electrode assembly 23 production efficiency.

With continued reference to fig. 9, in accordance with some embodiments of the present application, the electrode assembly winding apparatus 500 further includes a plurality of deviation rectification mechanisms 550 for rectifying the feed angles of the first pole piece 232 and the second pole piece 234, respectively.

Specifically, the deviation rectifying mechanism 550 is disposed between the feeding mechanism 540 and the first compounding mechanism 510 in the feeding path of the first pole piece 232 and between the feeding mechanism 540 and the second compounding mechanism 530 in the feeding path of the second pole piece 234, and before reaching the first compounding mechanism 510 and the second compounding mechanism 530, the first pole piece 232 and the second pole piece 234 conveyed by the feeding mechanism 540 pass through the deviation rectifying mechanism 550 to rectify the angle when the first pole piece 232 enters the first compounding mechanism 510 and rectify the angle when the second pole piece 234 enters the second compounding mechanism 530.

The deviation rectifying mechanism 550 may be two oppositely arranged passing rods, and a deviation rectifying space is formed between annular sides of the passing rods, so that the first pole piece 232 and the second pole piece 234 move towards the accurate feeding direction after passing through the deviation rectifying space.

By arranging the deviation correcting mechanism 550, the alignment degree of the first pole piece 232 and the second pole piece 234 during hot press lamination can be effectively ensured, and the electrode assembly can be further ensured to be wound accurately.

Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present application, and not for limiting the same; while the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art will appreciate that: the technical scheme described in the foregoing embodiments can be modified or some or all of the technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit of the embodiments, and are intended to be included within the scope of the claims and description. In particular, the technical features mentioned in the respective embodiments may be combined in any manner as long as there is no structural conflict. The present application is not limited to the specific embodiments disclosed herein, but encompasses all technical solutions falling within the scope of the claims.

Claims

1. An electrode assembly comprising a first separator, a first pole piece, and a second separator in a stacked arrangement;

the first pole piece is clamped between the first diaphragm and the second diaphragm, and is fixedly connected with part edges of two sides of the initial section of the second diaphragm along the width direction of the first pole piece.

2. The electrode assembly of claim 1, wherein the first separator is fixedly connected to a portion of the edges on both sides of the ending section of the second separator in the width direction.

3. The electrode assembly of claim 1 or 2, further comprising a second electrode sheet, a starting section of the second electrode sheet being fixedly connected to the second separator.

4. The electrode assembly of claim 3, wherein the ending segment of the second pole piece is fixedly connected to the second separator.

5. A battery cell comprising the electrode assembly of any one of claims 1-4.

6. A battery comprising the battery cell of claim 5.

7. An electrical device comprising the battery of claim 6 for providing electrical energy.

8. An electrode assembly winding method including a first separator, a first electrode sheet, and a second separator, which are stacked, comprising:

sequentially stacking the first diaphragm, the first pole piece and the initial section of the second diaphragm, and fixedly connecting partial edges of two sides of the initial section of the first diaphragm and the initial section of the second diaphragm along the width direction of the first pole piece;

and winding the first diaphragm, the first pole piece and the second diaphragm.

9. The electrode assembly winding method according to claim 8, further comprising:

and fixedly connecting part of edges at two sides of the ending section of the first diaphragm and the second diaphragm along the width direction.

10. The electrode assembly winding method according to claim 8 or 9, further comprising a second electrode sheet, wherein after fixedly connecting the partial edges of both sides of the first separator and the second separator starting section, further comprising:

and fixedly connecting the initial section of the second pole piece with the second diaphragm.

11. The electrode assembly winding method according to claim 10, further comprising:

And fixedly connecting the ending section of the second pole piece with the second diaphragm.

12. An electrode assembly winding apparatus, the electrode assembly including a first separator, a first pole piece, and a second separator, which are sequentially stacked, comprising:

the first compound mechanism is used for fixedly connecting the first diaphragm with part of edges on two sides of the second diaphragm starting section along the width direction of the first pole piece;

and the winding mechanism is arranged at the downstream of the first composite mechanism and is used for winding the first diaphragm, the first pole piece and the second diaphragm to form the electrode assembly.

13. The electrode assembly winding apparatus according to claim 12, wherein the first composite mechanism includes a first press-fit structure and a second press-fit structure disposed opposite to each other, the first press-fit structure and the second press-fit structure being mated for fixedly connecting partial edges of both sides of the starting section of the first separator and the second separator in the width direction.

14. The electrode assembly winding apparatus according to claim 13, wherein the first press-fit structure includes a pressing portion and a thermocompression bonding portion provided at both ends of the pressing portion in the width direction, and the thermocompression bonding portion is configured to protrude from the pressing portion, the thermocompression bonding portion being for thermocompression bonding partial edges of both sides of the starting section of the first separator and the second separator.

15. The electrode assembly winding apparatus according to claim 14, wherein the heat press composite part protrudes from the pressing part in a ring shape.

16. The electrode assembly winding apparatus according to any one of claims 12 to 15, further comprising a second electrode sheet, further comprising a second compounding mechanism disposed between the first compounding mechanism and the winding mechanism for fixedly connecting a starting section of the second electrode sheet with the second separator.